Magnetic recording apparatus

Abstract

A magnetic recording apparatus having a plurality of magnetic heads (111-118) by which data is written on and read from a magnetic medium (121-123) has a timing correction unit (3) that controls a suitable timing according to a predetermined characteristic of a selected magnetic head or disk apparatus and the density of logical ONE states in the data so that the data will be written on the magnetic medium under the timing controlled by the timing correction unit. Timing correction may also be provided according to whether the head is an inner or an outer head.

We claim: 
     
       1. An information recording apparatus, comprising: means for supplying data to be recorded;   transducer means for performing operations of recording the data on information recording media;   means for selecting said transducer means;   means for establishing outputs to control timing of operations of said transducer means according to predetermined characteristics of individual elements of said transducer means, and for providing said output during selection of corresponding ones of said transducer means;   timing correction means for controlling timing of the operations according to said output; and   recording control means for supplying the data from said data supplying means to said transducer means according to the timing controlled by said timing correction means.   
     
     
       2. The information recording apparatus according to claim 1, wherein said timing correction means controls the timing according to the predetermined characteristic of said transducer means and the density of logical ONE states in the data supplied by said data supplying means. 
     
     
       3. The information recording apparatus according to claim 2, wherein said information recording media is a magnetic recording disk and said transducer means is a magnetic head. 
     
     
       4. The information recording apparatus according to claim 2, wherein the control of said timing by said timing correction means caused by said density of logical ONE states is varied according to the predetermined characteristic of said transducer means. 
     
     
       5. A magnetic recording apparatus, comprising: a. a magnetic recording medium;   b. means for supplying digital data to be written on said magnetic recording medium;   c. a plurality of magnetic head means for writing the data from said data supplying means on said magnetic recording medium;   d. head selection means for selecting one out of said plurality of magnetic head means by which the data is written on said magnetic recording medium;   e. means for setting a timing correction corresponding to a characteristic of each said magnetic head means and providing a signal indicating the characteristic of each magnetic head means selected by said head selection means;   f. timing correction means for controlling the timing of writing the data according to the signal from said setting means; and   g. control means for transferring the data from said data supplying means to said magnetic head means selected by said head selection means according to the timing controlled by said timing correction means.   
     
     
       6. The magnetic recording apparatus according to claim 5, wherein said head selection means selects one of said plurality of magnetic head means when data is written on and read from said magnetic recording medium, further comprising means for synchronizing the phase of the data read from said magnetic recording medium by said control means. 
     
     
       7. The magnetic recording apparatus according to claim 5, wherein said data supplying means includes a memory to temporarily store the data. 
     
     
       8. The magnetic recording apparatus according to claim 5, wherein said setting means includes means corresponding to each said magnetic head means for switching the timing correction between predetermined states corresponding to the characteristic of each said magnetic head means. 
     
     
       9. The magnetic recording apparatus according to claim 8, wherein said switching means corresponding to each said magnetic head means is set to a state which generates a value for each signal to regulate control of said timing correction means. 
     
     
       10. The magnetic recording apparatus according to claim 8, wherein said magnetic recording medium is a rotatable magnetic hard disk, further comprising an arm which is movable toward the center of rotation of said magnetic hard disk supporting a first inner one of said magnetic head means comparatively close to said center and a second outer one of said magnetic head means comparatively farther from said center than said first head; and further means to provide different timing delays for inner and outer ones of said head means.   
     
     
       11. The magnetic recording apparatus according to claim 5, wherein said timing correction means includes a plurality of different delay elements and means for seelcting said delay elements according to the signal from said setting means. 
     
     
       12. The magnetic recording apparatus according to claim 5, wherein said timing correction means controls the timing according to the signal from said setting means and the density of logical ONE states in the data transferred from said data supplying means. 
     
     
       13. The magnetic recording apparatus according to claim 12, wherein the control of the timing by said timing correction means caused by said density of logical ONE states is varied according to the signal from said setting means. 
     
     
       14. The magnetic recording apparatus according to claim 5, further comprising a plurality of delay elements and a signal line to transfer the data from said data supplying means to said delay elements, whereby said head selection means selects said delay elements according to the logical states of the data transferred over said signal line and state of the signal from said setting means. 
     
     
       15. A timing correction method in a magnetic recording apparatus, comprising the steps of: determining a pattern peak shift characteristic of a magnetic read/write head;   making a comparison of the determined pattern peak shift with a reference range;   selectively associating a timing delay with the magnetic read/write head according to said comparison; and   recording digital data on a magnetic medium by the magnetic read/write head with the delay when the pattern peak shift ratio is substantially outside said range.   
     
     
       16. The timing correction method according to claim 15, further comprising the step of selectively associating said timing delay with the magnetic head according to said comparison and the density of logical ONE states of the data, so that the data will be recorded on a magnetic medium by the magnetic head with the delay when the pattern peak shift ratio is substantially outside the range and the density of logical ONE states is above a predetermined density. 
     
     
       17. The timing correction method according to claim 15, wherein said step of recording employs on the magnetic medium a rotatable magnetic hard disk and an arm which is movable toward the center of rotation of the magnetic hard disk supporting a first and inner magentic read/write head comparatively close to said center and a second and outer magnetic read/write head comparatively farther from said center than said first head so that both the first and second heads record on respective inner and outer annular portions of a single surface of the disk, further comprising the step of providing different data recording timing delays for the inner and outer heads. 
     
     
       18. The timing correction method according to claim 16, wherein said step of recording employs as the magnetic medium a rotatable magnetic hard disk and an arm which is movable toward the center of rotation of the magnetic hard disk supporting a first and inner magnetic read/write head comparatively close to said center and a second and outer magnetic read/write head comparatively farther from said center than said first head so that both the first and second heads record on respective inner and outer annular portions of a single surface of the disk; and further comprising the step of providing different data recording timing delays for the inner and outer heads.   
     
     
       19. A magnetic recording apparatus, comprising: a. a rotatable magnetic hard disk;   b. a plurality of magnetic heads including a first inner one comparatively close to the center of rotation of said magnetic hard disk and a second outer one comparatively farther from said center than said first head;   c. means to write and read digital data on and from inner and outer portions of one surface of said magnetic hard disk by said inner and outer heads, respectively,   d. a memory to temporarily store the data to be written on said magnetic hard disk;   e. means for selecting one out of said plurality of magnetic heads when the data is written on and read from said magnetic hard disk;   f. means for causing a timing correction corresponding to a location of each said magnetic head and providing a signal indicating the characteristic caused by the location of each magnetic head;   g. timing correction means including a plurality of different delay elements and gate means for selecting said delay elements according to the signal from said causing means and the density of logical ONE states in the data transferred from said memory to provide different timing delays for said inner and outer magnetic heads; and   h. read/write means to transfer the data from said memory to said magnetic head selected by said selecting means according to the timing provided by said timing correction means.   
     
     
       20. An information recording apparatus, comprising: means for supplying data to be recorded;   a plurality of transducer means for recording the data from said data supplying means on an information recording medium;   means for selecting one of said plurality of transducer means;   means for establishing timing corrections corresponding to characteristics of said plurality of transudcer means and for providing an output corresponding to a characteristic of each one of said plurality of transducer means selected by said selecting means;   timing correction means for controlling timing of the recording according to said output; and   recording control means for supplying the data from said data supplying means to said transducer means according to the timing controlled by said timing correction means.   
     
     
       21. The information recording apparatus according to claim 20, wherein said timing correction means controls the timing according to a predetermined characteristic of said transducer means and the density of logical ONE states in the data supplied by said data supplying means. 
     
     
       22. The information recording apparatus according to claim 21, wherein the control of said timing by said timing correction means caused by said density of logical ONE states is varied according to the predetermined characteristic of said transducer means. 
     
     
       23. An information recording apparatus, comrpising: means for selecting one of a plurality of transducer means for recording data on an information recording medium;   means for establishing timing delays corresponding to characteristics of the plurality of transducer means and for providing an output indicating a corresponding characteristic of each one of the transducer means selected by said selecting means;   timing correction means for controlling timing of the recording according to said output; and   recording control means for supplying the data to said transducer means according to the timing controlled by said timing correction means.   
     
     
       24. The information recording apparatus according to claim 24, wherein said timing correction means controls the timing according to a predetermined characteristic of the transducer means and the density of logical ONE states in the data supplied by said data supplying means. 
     
     
       25. The information recording apparatus according to claim 24, wherein the control of said timing by said timing correction means caused by said density of logical ONE states is varied according to the predetermined characteristic of said transducer means. 
     
     
       26. An information recording apparatus, comprising: means for selecting one of a plurality of transducer means for recording and reading data on information recording media;   means for selectively associating an output with each one of the plurality of transducer means according to characteristics of respective ones of the transducers, and for providing the corresponding said output during selection of each one of the transducer means by said selecting means;   timing correction means for controlling timing of the recording according to the output provided by said associating means; and   recording control means for supplying the data to the transducer means according to the timing controlled by said timing correction means.   
     
     
       27. The information recording apparatus according to claim 26, wherein said timing correction means controls the timing according to a predetermined characteristic of the transducer means and the density of logical ONE states in the data supplied by said data supplying means. 
     
     
       28. The information recording apparatus according to claim 26, wherein the control of said timing by said timing correction means caused by said density of logical ONE states is varied according to the predetermined characteristic of said transducer means. 
     
     
       29. A magnetic recording apparatus, comprising: magnetic head means including a plurality of transducer means, for writing data on magnetic recording media;   head selection means for selecting one of said transducer means to write the data on said magnetic recording media;   means for setting timing corrections corresponding to a characteristic of each said transducer means and providing a signal indicating the characateristic of each transducer means selected by said head selection means;   timing correction means for controlling the timing for writing the data according to the signal from said setting means; and   control means for transferring the data to said magnetic head means selected by said head selection means according to the timing controlled by said timing correction means.   
     
     
       30. The magnetic recording apparatus according to claim 29, wherein said head selection means selects one of said plurality of magnetic head means when data is written on and read from said magnetic recording medium, further comprising means for synchronizing the phase of the data read from said magnetic recording medium by said control means. 
     
     
       31. The magnetic recording apparatus according to claim 29, wherein said setting means includes means corresponding to each said magnetic head means for switching the timing correction between predetermined states corresponding to the characteristic of each said magnetic head means. 
     
     
       32. The magnetic recording apparatus according to claim 31, wherein said switching means corresponding to each said magnetic head means is set to a state which generates a value for each signal to regulate control of said timing correction means. 
     
     
       33. The magnetic recording apparatus according to claim 29, wherein said timing correction means controls the timing according to the signal from said setting means and the density of logical ONE states in the data transferred from said data supplying means. 
     
     
       34. The magnetic recording apparatus according to claim 29, further comprising a pluraltiy of delay elements and a signal line to transfer the data to said delay elements, whereby said head selection means selects said delay elements according to the logical states of the data transferred over said signal line and state of the signal from said setting means. 
     
     
       35. A magnetic recording apparatus, comprising: a plurality of magnetic head means for writing data on magnetic recording media;   head selection means for selecting one of said plurarity of magnetic head means to write the data on said magentic recording media;   means for setting timing corrections corresponding to characteristics of each of said magnetic head means and providing a signal indicating the characteristic of each magnetic head means selected by said head selection means;   timing correction means for controlling the timing for writing the data according to the signal from said setting means; and   control means for transferring the data to said magnetic head means selected by said head selection means according to the timing controlled by said timing correction means.   
     
     
       36. The magnetic recording apparatus according to claim 35, wherein said head selection means selects one of said plurality of magnetic head means when data is written on and read from said magnetic recording medium, further comprising means for synchronizing the phase of the data read from said magnetic recording medium by said control means. 
     
     
       37. The magnetic recording apparatus according to claim 35, wherein said setting means includes means corresponding to each said magnetic head means for switching the timing correction between predetermined states corresponding to the characteristic of each of said magnetic head means. 
     
     
       38. The magnetic recording apparatus according to claim 37, wherein said switching means corresponding to each said magnetic head means is set to a state which generates a value for each signal to regulate control of said timing correction means. 
     
     
       39. The magnetic recording apparatus according to claim 35, wherein said timing correction means controls the timing according to the signal from said setting means and the density of logical ONE states in the data transferred from said data supplying means. 
     
     
       40. The magnetic recording apparatus according to claim 35, further comprising a plurality of delay elements and a signal line to transfer the data to said delay elements, whereby said head selection means seelcts said delay elements according to the logical states of the data transferred over said signal line and state of the signal from said setting means. 
     
     
       41. A magnetic recording apparatus, comprising: a plurality of magnetic head means for performing operations of writing data on magnetic recording media;   head selection means for selecting one of said plurality of magnetic head means to perform operations with the data on said magnetic recording media;   means for setting an output indicating a resolution characteristic of each magnetic head means and for providing a corresponding output for each one of said magnetic head means selected by said head selection means;   timing correction means for controlling the timing for operations of the magnetic head means for writing and reading the data, according to the output from said setting means; and   control means for transferring the data to said magnetic head means selected by said head selection means according to the timing controlled by said timing correction means.   
     
     
       42. The magnetic recording apparatus according to claim 41, wherein said head selection means selects one of said plurality of magnetic head means when data is written on and read from said magnetic recording medium, further comprising means for synchronizing the phase of the data read from said magnetic recording medium by said control means. 
     
     
       43. The magnetic recording apparatus according to claim 41, wherein said setting means includes means corresponding to each said magnetic head means for switching the timing correction between predetermined states corresponding to the characteristic of each said magnetic head means. 
     
     
       44. The magnetic recording apparatus according to claim 43, wherein said switching means corresponding to each said magnetic head means is set to a state which generates a value for each signal to regulate control of said timing correction means. 
     
     
       45. The magnetic recording apparatus according to claim 41, wherein said timing correction means controls the timing according to the signal from said setting means and the density of logical ONE states in the data transferred from said data supplying means. 
     
     
       46. The magnetic recording apparatus according to claim 41, further comprising a plurality of delay elements and a signal line to transfer the data to said delay elements, whereby said head selection means selects said delay elements according to the logical states of the data transferred over said signal line and state of the signal from said setting means.